Batteryless ringing device



Dec. 20, 1949 w. J. MULDOON BATTERYLESS RINGING DEVICE 2 Sheets-Sheet 1Filed Nov. 22, 1946 l m mmmm u INVENTOR. WiLLlAM J. MULDOON BY I Dec.20, 1949 Filed Nov. 22, 194$ FIG. 2

W- J- MULDOON BATE ERYLESS RINGING DEVICE 2 Sheets-Sheet 2 INVENTOR.WILLIAM J. MULDOON I flk ywmlzf AT TOR NEYS Patented Dec. 20, 1949 U N IT ED STATES PAT ENT' 2,492,056

BATTERYLESS RINGIN'G DEVICE. William J'. Muldoon, Garden City,N..Y.,.assig'n0l';

by: mesne assignments, to The Wheeler Insu lated Wire Company,Incorporated, Bridgeport,- Qonn., a corporation of Delaware, ApplicationNovember 22, 1946, Serial No. 711,505 Claims. (Cl. 179-87) Thepresentinvention relates to; signaling devices, and more particularlytoabatteryless ringing device for a telephone system.

The development oi sound-powdered telephone units has made it. possibleto communicate over short distances without; the use of external sourcesof power. For example, my prior application, Serial No.7 670,585,describesv an inexpensive and efficient sound-powdered transducer whichisespecially suitable for toytelephones, inter-officetelephones, and;the like. In such a system it is desirable to. have aringing unit andsince the,- telephone system requires no battery, it is likewisedesirable toprovide a ringing unit in which. a battery is; not required.

Accordingly, the principal object of the present invention is to providea batteryless signaling unit which is especially adaptable for telephonesystems of this type.

.In the accompanying drawings, Fig. 1 is an elevation of a telephoneinstrument embodying a signalingunit. According to the presentinvention; Figs. 2 and 3 are plan. views or. the ringing unit; Figs. 4and 5-are detail views of the, operating device; andv Fig. 6 is asectional detail view or" the transducer.

The illustrated embodiment of the invention comprises a'ringing unit fora pair of telephones, here shown as a pair of toy telephones. Eachtelephone instrument 2 is. provided with. a soundpowered transducerpreferably, although not necessarily of the type described in myabove-mentioned prior application. The unit may be conveniently mountedin a. hand-set 4 of conventional form.

The ringing. system for the telephones comprises two synchronous wirereeds 5, one for each telephone instrument, together with manual meansfor vibrating the reed at the transmitting end, whereby the reed at thereceiving end will be caused to vibrate in synchronism therewith.Associated with each reed. is a, bell so arranged that the receivingreed will strike it and give a signal. For a toy telephone which, isdesigned to simulate a standard telephone unit, the reed is convenientlyarranged to be actuated by a rotary dial 6;

Each telephone instrument has a metal base 3. Mounted onthe base is atransducer l0, which is substantially identicalirr structure with thesound-powdered transducer described in my prior application. As shown inFig. 6, it comprises two magnets of high coercive force indicated at 12and carrying between them a magnetic armature I4. A coil l5 surroundsthe armature. The

. 2 magnets are: provided with suitable pole pieces it extending. intoproximity with'the armature. near its end. This type. of; unit isparticularly suitable although any conventional vibrating magneticarmature typetransducer-maybe used.

The armature is, instead of being. connected with an acoustic;diaphragm, is provided at its end with an ear ZE! having; a hole.through which passes the vibratory wire reedi. Asshown in Figs. 2 andoneendot the. reed is:-Supp0rtecl' in a frame 25 andQt-he free endextends out.-. wardly into. proximity with a vbeill- 25.. If thereed i5is vibrated manually. acurrent generated in the coil 4 Sci thetransduceri andthus. a signal is transmitted to the similar unit ill-oithe. re.-

ceiving telephone. The ourrenttransmitted tov the receiving unit causesvibration- 0f its armature and its reed 5, whichv thereby strikesthe-bell, and gives the desired signal. The reeds 22 are preferably ofsuch characteristicsthat the reed.-

armature systems resonate at. about cycles per second, and the two reedsshould. be tuned; approximately within 5 cycles of. each other formaximum sensitivity.

As heretofore noted, the reed 5may-be vibrated manually in any desiredmanner.- In-a toy unit the vibration of the. reed is. preferablyinitiated by rotation of the. dial, 6. Itv islikewise. desirable to,move the bell. 26 of the transmitting; unit out of the way of the reedso thatthe transmitting reed will. not be damped by engagement with itshell. with a bracket 352. having aportionSZ extending toward the reed.P'i-votedv on. the part 32 is a dog 3 which is adapted to engage. the.reed, upon a clockwise rotation of the dial; The, bellis mounted, onv anarm 36 pivoted to. the base. at 33 and normally held by spring 40'.against a stop di' in, the positionshown in. Fig- 2. As the dial isturned, the dog 34 moves the bell and reed to a position asindicatedinlii'g. 3, atwhich point a bracket M deflects. the reeddownward to a point where further motionv of the dog 34 releases thereed. When the dog moves out. of engagement with the reed, thev reed.snaps back with a whiplik'e motion and. then. vibrates for av number oicycles. Thebell'. is fi'ee toreturn under the influence, of the springW51 because. of the high inertia of the, b e1l'.however, as comparedwith that of the reed, the reed will undergo several vibrations beforethe bell returns to a position where the reed will engage with it.Accordingly, the hell does not damp the reed until the vibration of thereed is substantially completed. The electrical signal generated in theTo these ends, the dial shaft is providedv transducer by vibration ofthe reed is transmitted over the line to the transducer In of thereceiving telephone, thus causing the reed of the receiving unit tovibrate in unison with that of the transmitter. The receiving reedstrikes the bell several times and gives the desired signal.

The electrical connections may be made in any suitable way whereby thetransducer units 4 are used for talking and the units ID for ringing. Inmost systems and particularly for toy telephones, it is desirable tohave a single line connecting both units. The diagram for the preferredsimple unit is illustrated in Fig. 2, in which the sound-poweredtransducer 4 and the reed transducer in of a single unit are connectedin series. The base of each unit is provided with a terminal block 43having terminals 44 and 46 to which the line wires 48 and 50 arerespectively connected. The coil l of the unit It) is connected betweenthe terminal 44 and a connector 52. As indicated at 54, one side of thecoil is grounded to the metal base 3. The acoustic transducer unit isconnected between the terminal 52 and the terminal 46 by a suitable cord56. As heretofore noted, the unit may be mounted in a suitable handset 4to be carried in the cradle 69 at the top of the instrument.

The connections thus far described place the two acoustic transducersand the two reed transducers of both instruments all in series. Sincethe toy ringing unit herein specifically described operates at a verylow power level, it is desirable to exclude the acoustic transducer 4 ofthe transmitting telephone from the circuit at the time the ringingoperation is being carried out. To this end the terminal 46 is providedwith an extension 62 in proximity with the bell. When the bell is swungabout its pivot 38 by the dog 34, the extension 62 is engaged by thebell. As shown in Fig. 1, this extension is inclined and is ofspringlike material so that it is engaged by the bell for a considerableportion of the ringin cycle. It has been heretofore noted that one sideof the coil, corresponding electrically to the terminal 52, is groundedto the base. Thus when the bell engages the contact 62, the acoustictransducer unit 4 is short-circuited. The short-circuit path runs fromthe terminal 52 through the ground connection 54, the pivot 38, the arm36, the bell 26 and the contact 62, to the terminal 46. Thisconstruction, which is a simple one, results in short-circuiting of theacoustic transducer at the transmitting end during the ringing cycle.

It will be understood that cradle switches 0perated by the handsets, orsimilar devices known to those skilled in the telephone art, may be usedto short-circuit both acoustic transducers. Such switches would be usedin more expensive units but for a toy system the simple means forshortcircuiting the transducer at the transmitting end is usuallyadequate.

In its broader aspects, the present invention comprises anelectro-mechanical transducer having a vibrating reed. Two of theseunits are used, one for each telephone of the pair. The reed which is atthe transmitting end is vibrated mechanically. It will be understoodthat any suitable means may be used for vibrating the reed. For a toytelephone the rotary dial is pror contact engaged by the vided in orderto simulate an actual telephone, and the dial is also conveniently usedto vibrate the reed. It will be understood that the energy supplied tothe reed for a single operation of the dial is rather small. Theinvention, however, is not limited to the particular means for settingthe reed in vibration, and other means which will maintain the reed insustained vibration may be preferred for telephones other than toys, aswill be clear to those skilled in the art.

Having thus described my invention, I claim:

1. A signaling unit comprising an electromechanical transducer having anarmature, a permanent magnet and a winding, a vibratory reed connectedwith the armature, a bell adapted to be struck by the reed, manual meansfor flexing the reed, and means operated by said manual means for movingthe bell out of engagement with the reed during vibration thereofsubsequent to such flexing.

2. A signaling unit comprising an electromechanical transducer having anarmature, a permanent magnet and a winding, a vibratory reed connectedwith the armature, a bell adapted to be struck by the reed, manual meansfor manually flexing the reed and for moving the bell therewith out ofthe range of motion of the reed, whereby the reed when set intovibration by manual flexure, is not clamped by the bell.

3. A telephone unit comprising two transducers connected in series, oneof said transducers being an acoustic device and the other having avibratory reed, means for manually setting the reed into vibration togenerate a signal, and means operated by said manual means forshort-circuiting the acoustic transducer during said period of signalgeneration.

4. A telephone unit comprising two transducers connected in series, oneof said transducers being an acoustic device and the other having avibratory reed, means for manually setting the reed into vibration, abell to be rung by the reed. means operated by said manual means to movethe bell out of engagement with the reed and a bell to short-circuit theother transducer.

5. A signaling unit comprising an electromechanical transducer having anarmature, a vibratory reed connected with the armature, a permanentmagnet and a winding, a bell adapted to be struck by the reed, manualmeans for flexing the reed, and a pivotal mounting for the bell, andmeans to cause the bell to be swung to a position out of engagement withthe reed when the reed is manually flexed.

WILLIAM J. MULDOON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 251,097 Currier Dec. 20, 1881289,834 Herzog Dec. 11, 1883 372,404 Deprex et al. Nov. 1, 18871,262,359 Kropp Apr. 9, 1918 2,192,216 Woodruff Mar. 5, 1940 2,293,166Olson Aug. 18, 1942

